Park et al. International Journal of Mental Health Systems 2014, 8:22 http://www.ijmhs.com/content/8/1/22

RESEARCH Open Access Associations between changes in the pattern of methods and rates in Korea, the US, and Finland Subin Park1, Myung Hee Ahn2, Ahrong Lee2 and Jin Pyo Hong2*

Abstract Background: The lethality of the suicide method employed is a strong risk factor for the completion of suicide. We examined whether annual changes in the pattern of is related to annual changes in suicide rates in South Korea, the (US), and Finland. Methods: We analyzed annual data from 2000–2011 for South Korea and Finland, and 2000–2010 for the US in order to examine trends in the rates and methods of suicide. Data on suicide methods were obtained from the World Health Organization (WHO) mortality database. Results: Along with an annual rapid increase in suicide rates, the incidence of increased steadily while suicide by self- steadily decreased in South Korea. In the US, along with an annual increase in suicide rates, the proportion of committed by hanging increased while those committed with the use of steadily decreased. In Finland, annual changes in the suicide rate and suicide method were not statistically significant during the study period. Conclusions: Our present findings suggest that the increased use of specific lethal methods for suicide, namely hanging, is reflected in the increased suicide rates in the Korean and the US populations. The most effective approach for reducing overall suicide rates may be the implementation of population-based initiatives that reduce both the accessibility (e.g., access to firearms) and the social acceptability (e.g., effective and responsible regulations for reporting suicide) of lethal methods of suicide. Keywords: Suicide, Method, Hanging

Background behavior with sharp objects having lower fatality (less In 2012, South Korea had the highest suicide rate of all than 5%) [2,3]. National studies on suicide indicate that countries in the Organization for Economic Cooperation the preferred suicide method varies between countries. and Development (OECD) [1]. In recent years, suicide Some patterns are well known, such as the high propor- rates have increased rapidly and steadily in South Korea: tion of suicides in the United States [4] and the in 1990 an average of 9.8 suicides per 100,000 individ- prevalent suicide in Asian countries in the uals were observed, and in 2012 the rate was 33.5 1990s [5]. Hanging was the most prevalent suicide suicides per 100,000 individuals. methods in many countries including European coun- The lethality of the chosen suicide method is a strong tries [6], Australia [7], and Canada [8]. In South Korea, risk factor for suicide completion [2]. Use of firearms use of firearms is very rare, because of strict government and hanging are two of the most lethal suicide with over restrictions limiting firearms [9]. Hence, a trend toward 80% case fatality while self-poisoning and self-injurious increased use of hanging among Koreans may partially explain the increased suicide rates. In our present study, we examined whether annual * Correspondence: [email protected] 2Department of Psychiatry, Asan Medical Center, Ulsan University College of changes in the pattern of suicide methods is related to Medicine, 388-1 Pungnap-2dong, Songpa-gu, Seoul 138-736, South Korea the annual change in suicide rates in South Korea. We Full list of author information is available at the end of the article

© 2014 Park et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Park et al. International Journal of Mental Health Systems 2014, 8:22 Page 2 of 7 http://www.ijmhs.com/content/8/1/22

used suicide victims in the United States and Finland as cause of death was 100% in all three countries. The rate of the comparison group for an investigation of trends in ill-defined causes in cause-of-death registration was 15.4% suicide rates and methods in South Korea. The United in South Korea, 6.7% in the United States, and 2.4% in States, where guns are more available, is selected to Finland in 2010. examine the effect of use of firearms, one of the most le- We performed Spearman correlation analyses to assess thal method, on suicide rates. Finland is selected because trends in suicide rates over the 12-year period and it is the first country to establish a research-based com- potential correlations between specific suicide methods prehensive national program for , and suicide rates. All statistical analyses were performed which significantly decreased national suicide rates and using SPSS (version 21.0; SPSS Inc., Chicago, IL), with earned praises from around the world [10]. In the statistical significance defined as an alpha level of 0.05/ United States, the suicide rate has increased steadily (5 types of suicide methods × 3 countries) = 0.0033. since 2000 (10.4 suicides per 100,000 individuals), with 12.6 suicides per 100,000 individuals in 2010. However, Results the extent of change in suicide rates was not as rapid Annual suicide rates in South Korea and Finland in the United States compared with South Korea. In between 2000 and 2011 as well as annual suicide rates in Finland, the suicide rate has decreased since 1990, with the United States between 2000 and 2010, are shown 30.3 suicides per 100,000 individuals in 1990, 22.5 sui- in Figure 1. During this period, suicide rates for males in cides per 100,000 individuals in 2000, and 16.9 suicides South Korea rapidly increased from 18.8 to 43.3 suicides per 100,000 individuals in 2011 [11]. We hypothesize per 100,000 individuals, and from 8.3 to 20.1 suicides that the increased use of more lethal methods such as per 100,000 individuals for females. On the other hand, hanging and firearms may be associated with the in- suicide rates among the Finnish population decreased crease in the total suicide rates, and that this association from 34.56 to 26.76 suicides per 100,000 individuals for may be more prominent in countries where the use of males and 10.94 to 7.29 suicides per 100,000 individuals less lethal method is replaced by more lethal method, for females. The United States suicide rate slightly but than in countries where the use of one specific lethal steadily increased from 17.1 to 20.2 suicides per 100,000 method of suicide is replaced by other specific lethal individuals for males and from 4.0 to 5.2 suicides per method. 100,000 individuals for females. In South Korea, self-poisoning was the most common Methods method of suicide for both males and females until the We analyzed annual data during the period 2000–2011 early 2000’s. The rate of self-poisoning significantly and to examine trends in suicide rates and suicide methods steadily decreased since 2001 (r = −0.96, P < 0.001 for both in three countries. Data on suicide rates and methods males and females). In contrast,therateofhangingsignifi- among people aged 10 years over were obtained from cantly increased (r = −0.96, P < 0.001 for males and r = 0.93, the World Health Organization (WHO) mortality data- P < 0.001 for females), and hanging has been the most com- base [11]. The most recent data were from 2011 for mon method of suicide among Korean males since 2003 South Korea and Finland, and from 2010 for the United and among Korean females since 2005 (Figure 2). For States. Suicide methods were classified into five categor- both Korean males and females, there was a significant ies according to the ICD-10 codes: self-poisoning (X60– positivecorrelationbetweensuiciderateandtherateof X69), hanging (X70), firearms (X72–74), jumping from a hanging (r = 0.90, P < 0.001 and r = 0.95, P <0.001, re- high place (X80), and others (X71, X75–X79, X81–X84). spectively), and a negative correlation between suicide The WHO obtains data on deaths that includes age, rate and both the rate of poisoning (r = −0.88, P < 0.001 sex, and cause of death, as reported annually by member and r = −0.98, P < 0.001, respectively) and the rate of states through civil registration systems (e.g., the Korean other methods (r = −0.92, P < 0.001 and r = −0.95, P < 0.001, National Statistical Office, the National Center for respectively). Health Statistics of the United States, and the Statistics During the study period, firearms were the most Finland), and compiles the data in the WHO mortality common method of suicide in American males; how- database. Based on country-reported data and the use of ever, the rate of suicide by firearms decreased signifi- additional data sources such as population censuses and cantly (r = −0.92, P = 0.001), and the rate of hanging household surveys, the WHO and its partners regularly increased significantly (r = 0.97, P < 0.001) in the United estimate key mortality statistics to improve data compar- States. Between 2001 and 2010, poisoning was the most ability across countries and years. In addition, the WHO common suicide method among American females. estimates the completeness and coverage of reported data, During the same period in the United States, firearms and assesses the quality of cause-of-death data. According were the second most common suicide method among to the WHO, the rate of civil registration coverage of American females, but the rate decreased significantly Park et al. International Journal of Mental Health Systems 2014, 8:22 Page 3 of 7 http://www.ijmhs.com/content/8/1/22

Figure 1 Annual trends in suicide rates in South Korea, the United States, and Finland.

(r = −0.86, P = 0.001). In contrast, the rate of hanging suicide rates. This hypothesis is supported by the find- increased significantly and steadily (r = 0.96, P < 0.001), ings of our present study, at least in case of South Korea. but the rate of jumping decreased significantly (r = −0.90, The proportion of highly lethal methods, namely hang- P < 0.001) among American females (Figure 3). ing, increased, and the proportion of less lethal methods Among both American males and females, there was a such as self-poisoning decreased among South Korean significant positive correlation between the suicide rate males and females, which were accompanied by a trend and the rate of hanging (r = 0.83, P = 0.002 and r = 0.96, of increased annual suicide rates. This association be- P < 0.001, respectively), and a negative correlation be- tween the proportion of suicides by hanging and annual tween the suicide rate and the rate of suicide by firearms changes in overall suicide rates was less prominent in (r = −0.80, P = 0.003 and r = −0.84, P = 0.001, respect- the United States where the use of firearms, which is an ively). In addition, there was a significant negative cor- even more lethal method, was replaced by hanging. This relation between the suicide rate and the rate of suicide association was not observed in Finland, where annual by jumping in American females (r = −0.89, P < 0.001). changes in the suicide rate and the pattern of suicide In Finland, the most common method of suicide in methods were not prominent during the study period. males was hanging, while self-poisoning was the most It should be noted that drug poisoning was a suicide common method of suicide in Finnish females during method that has been commonly used in the past in the study period. The trends for the changes in suicide South Korea, but has become less available in recent method were not statistically significant for both males years due to strict regulations [12], and this may explain and females in Finland, and there was no significant an increased use of hanging. In 2000, the Pharmacist correlation between suicide rate and the rate of any Law was revised to restrict dispensing of prescription specific suicide methods (Figure 4). medications and in 2005, the Agrochemicals Control Act was revised to limit pesticide sales and purchases Discussion more strictly. These findings suggest that government We hypothesized that an increased use of a specific le- restrictions limiting pesticide purchases and drug pre- thal suicide method was related to an increase in overall scriptions are effective strategies for reducing suicide by Park et al. International Journal of Mental Health Systems 2014, 8:22 Page 4 of 7 http://www.ijmhs.com/content/8/1/22

Figure 2 Trends in the suicide methods employed by Korean males and females between 2000 and 2011.

these methods [13]. However, challenges remain for the slow, painful, and messy method that needed technical prevention of because of the difficulty knowledge for implementation. Authors suggested that of regulating and limiting the means to do so [14]. prevention strategies should focus on countering percep- With regard to the rapid increase in suicide by hanging tions of hanging as a clean, rapid, and painless method in South Korea since 2005, one consideration is the ability that is easily implemented [21]. Media could contribute to of celebrity suicides to induce copycat suicides, particu- generate negative social perceptions of hanging [18]. Thus, larly in females [15]. The media’s reporting of suicide and suicide prevention agencies must work with the media to its fictional portrayal on television are known to influence reduce the socio-cultural acceptability of hanging. In suicidal behavior, particularly the choice of method used South Korea, which has the highest Internet penetration [16-18]. Media guidelines for the sensational reporting of rate in the world [22], web-based programs to reduce the suicide are needed to reduce the portrayal of fictional sui- socio-cultural acceptability of hanging may be also effect- cides by lethal methods [19]. Suicide by hanging might be ive. However, even if hanging suicides decreased by de- influenced by altered public perception of its acceptability creasing social acceptability of this lethal method, it could [20]. Previous qualitative study of 22 suicide attempters be replaced by another lethal method such as jumping that included 8 respondents who had attempted hanging and charcoal burning. Therefore, for an overall decrease showed that hanging was adopted for two main reasons, in suicide rates, there is a need to adopt comprehensive, the anticipated nature of a death from hanging and acces- population-based approaches involving efforts to raise sibility [21]. Suicide attempters favoring hanging consid- awareness about suicide prevention, reinforcement of so- ered it as a clean, rapid and painless method with little cial safety nets, promotion of socio-cultural beliefs that awareness of dying and an easy method without the need discourage suicide, and adequate prevention and treat- of planning or technical knowledge. In contrary, respon- ment of depression and , proven risk factors dents who rejected hanging recognized that it could be for suicide [23]. Park et al. International Journal of Mental Health Systems 2014, 8:22 Page 5 of 7 http://www.ijmhs.com/content/8/1/22

Figure 3 Trends in the suicide methods employed by American males and females between 2000 and 2010.

Firearms were the most common method of suicide suicide by firearms was offset by an increase in suicide among American males and the second most common by hanging, another lethal method, which resulted in no method among American females. In the United States, change in the overall suicide rate in the American several firearm policies have been enacted to limit access population. to firearms, especially for underage youth. In 1994, a In Finland, the most common suicide methods were federal law established 18 as the minimum legal age for hanging in males and self-poisoning in females. In 1985, the possession or purchase of handguns, including sales Finland established a research-based comprehensive na- by gun owners who are not licensed dealers. American tional program for suicide prevention [10]. The suicide states vary in their requirements for gun ownership pro- rate continued to increase until 1990, but then decreased hibition laws, such as banning of minors and people by 20% between 1991 and 1996, and has been declining with history of felony, domestic violence offence, and ever since. A comprehensive national program for sui- mental or substance use problems [24]. Furthermore, cide prevention in Finland included efforts to raise gun safe storage laws, often referred to as child access awareness about suicide prevention (e.g., recognizing the prevention (CAP) laws, were enacted to prevent young warning sign of suicide), efforts to reduce the social ac- people from gaining access to firearms. Most laws re- ceptability of suicide (e.g., effective and responsible regu- quire gun owners to keep their guns in locked storage. A lations for reporting suicide), and efforts to limit the previous study demonstrating the effectiveness of CAP accessibility of a specific method of suicide (e.g., limiting laws [25] found that the restriction of access to firearms access to firearms) [10]. Such comprehensive population- is at least somewhat effective in decreasing the incidence based approaches may have helped decrease suicide of suicide by firearms and overall suicide rates in youth. attempts by all means, rather than only decrease sui- Increased waiting period for the obtainment of handgun cides attempts by specific methods, leading to an overall reduced suicide by firearm use among American adults decrease in suicide rates. However, because the trends over the age of 55 [26]. However, the reduction in for changes in suicide method were not significant Park et al. International Journal of Mental Health Systems 2014, 8:22 Page 6 of 7 http://www.ijmhs.com/content/8/1/22

Figure 4 Trends in the suicide methods employed by Finnish males and females between 2000 and 2011. during the study period, we could not conclude with but replacement by another lethal method (e.g., hanging) certainty that the decreased incidence of suicide at- may lead to no overall decrease in the suicide rate. In tempts using lethal methods was related to the decrease addition, limiting access to relatively less lethal methods in overall suicide rates in this country. of suicide (e.g., drugs) can be easily replaced by more We must interpret the results of this study within the readily available and lethal methods of suicide (e.g., hang- context of the following limitations. First, government ing). Therefore, the most fruitful approach to reducing case registries may underestimate the number of deaths overall suicide rates may be through population-based due to suicide because many suicides may have been initiatives that reduce both the accessibility and the social classified as “undetermined” deaths [27]. Second, al- acceptability of lethal methods of suicide. though our focus was on the impact of suicide methods on annual changes in suicide rates, various other factors Competing interests may have influenced the suicide rates, including social None of the authors have any financial interest in the study, or any other situations such as economic crises and celebrity suicides, conflict of interest. which were not considered. Finally, subgroup analysis according to the ethnicity/race was not available for the Authors’ contributions JPH designed the study, supervised the data collection, and assisted with heterogeneous United States population. writing the article. SP wrote the paper and carried out the statistical analysis. AL and MHA acquired the data and assisted with writing the article. All Conclusions authors read and approved the final manuscript. Our present findings suggest that the increased use of hanging as a suicide method in South Korea is related to Acknowledgements an increase in the overall suicide rate. Limiting access to This work was supported by the Korea Healthcare Technology R&D project, Ministry of Health & Welfare, Republic of Korea (grant number A120051) and by lethal methods of suicide (e.g., firearms) is an effective the Basic Science Program through the National Research Foundation of Korea strategy for reducing suicide by that particular method, (NRF) Grant funded by the Korean Government(MSIP) (No. 2013R1A1A3008158). Park et al. International Journal of Mental Health Systems 2014, 8:22 Page 7 of 7 http://www.ijmhs.com/content/8/1/22

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